Exchange Mail Footer and Disclaimer when sending iPhone/iPad

We have a corporate mail footer designed in html and it is including images. It works fine when i send mail from Outlook or OWA but when i send an email from my iOS devices our corporate mail footer is shown as plain text. Briefly, i send email from outlook to you and you see my email and footer normal. But when i send email from iphone to you, you see my footer as plain text so you can't see our images.

I don't know if it has a solution or not but i think i can find anyone encountered this problem before.

Thanks